Noiseless typewriter or the like



Oct. 9, 1962 E. J. GALLAGHER, JR 3,057,450

NOISELESS TYPEWRITER OR THE LIKE Filed March 7, 1961 3 Sheets-Sheet 1 INVENTOR.

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0&9, 1962 E. J. GALLAGHER, JR 3,057,450

NOISELESS TYPEWRITER' OR THE LIKE 5 Sheets-Sheerl 2 Filed March 7, 1961 In, 11, a'

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Oct. 9, 1962 E. J. GALLAGHER, JR 3,057,450

NoIsELEss TYPEWRITER 0R 'rx-1E LIKE Filed March 7, 1961 s sheets-sheet 5 j? A n INVENTOR. 4.9 ffgdwzg/ifw ATTORNEYS.

Iiatented Oct. 9, 1962 3,057,450 NUISEIJESS TYPILWRIIER R THE LIKE Edward J. Gallagher, Jr., 3501 Ednor Road, Baltimore 18, Md. Filed Mar. 7, 1961, Ser. No. 94,000 3 Claims. (Cl. 197-147) This invention relates to a sound dampened typewriter or other piece of equipment or machinery, and one of the personal objects of the present invention is to provide a means for permitting a typewriter or the like to be used or operated in such ya manner that the usual noises are eliminated or dampened or minimized.

This invention has as a further object to provide a means whereby a typewriter platen is constructed so that sounds or noises will be mutiied or dampened so that the typewriter can be quietly operated or used.

And the invention has as a still further object to provide a means whereby sounds from the normal use of a typewriter or other piece of equipment or machinery will be dampened or reduced, the present invention including a construction that embodies a plurality of members certain of which are made of sound proofing or sound deadening material, and wherein there is provided in certain of the members a plurality of apertures and passageways which provide a means whereby the sound waves are effectively muffled or dissipated, as for example when the keys of the typewriter are being manually depressed during the usual typing that is normally carried out on the typewriter or other piece of equipment.

A further object of the present invention is to provide a device which will be exceedingly simple in construction and which may accordingly be produced at moderate cost.

Other and incidental objects will appear hereinafter.

In the drawings:

FIGURE l is a longitudinal sectional view taken through a typewriter platen, constructed according to the present invention.

FIGURE 2 is a sectional view taken on the line 2-2 of FIGURE 1.

FIGURE 3 is a sectional View taken on the line 3-3 of FIGURE 1.

FIGURES 4 through 7 are fragmentary perspective views, with parts broken away and in section, showing certain of the apertured members that form part of the platen.

FIGURE 8 is a perspective view showing the partition or intermediate element that is arranged in the platen.

FIGURE 9 is an elevational View of one of the frustoconical inserts for the platen.

FIGURE 10 is asemi-diagrammatic fragmentary elevational view showing a portion of a typewriter constructed according to the present invention.

FIGURE 1l is a sectional view taken on the line 1.1-11 of FIGURE 1G.

FIGURE l2 is a side elevational view illustrating a typewriter constructed according to the present invention.

FIGURE 13 is a fragmentary perspective View taken generally on the line 13-13 of FIGURE 12.

FIGURE 14 is a sectional View taken generally on the line 14-14 of FIGURE 12.

Referring in detail to the drawings, the numeral 20 indicates a platen which may be used with a typewriter such as the typewriter 21, FIGURE 10, and as shown in FIGURE 1 the platen 20 is mounted on a shaft 22 that is adapted to be made of a suitable metal, and the interior of the shaft 22 is hollow as indicated by the numeral 23. A suitable acoustical material such as liber-glass as indicated bythe numeral 19 is arranged on the shaft 22. The shaft 22 is provided with a plurality of spaced apart apertures or openings 24- therein, and the numeral 25 indicates the usual hand knob which is adapted to be secured to the shaft 22 in any suitable manner, as for example by means of a set screw 26, and the knob 25 can be used for rotating the shaft 22.

The platen is shown to comprise a pair of spaced parallel similar end members 27 of circular formation, and these end members 2.7 are adapted to be made of sound deadening material and are provided with spaced apart apertures or openings 28 therein. These end members 27 are shaped to include shoulders 29, and the numeral St) indicates a partition that is interposed between the pair of end members 27, the partition 30 being of circular formation and being shaped to include shoulders 31 on the opposite faces thereof. The partition 30 is provided with a plurality of spaced ports or openings or apertures 32, and there is provided in the center of the partition 30 an enlarged opening 33 through which extends the shaft 22, and the -shaft 22 has the acoustical material 19 thereon.

It will be seen that the partition 30 defines on opposite sides thereof within the platen a pair of separate compartments or chambers, and arranged in each of these chambers is a generally cylindrical collar 34, FIGURE 6, and the interior of each of the collars 34 is hollow or open for the projection therethrough of a portion of the shaft 22. There is provided in the inner surface of each collar 34 -a plurality of spaced parallel longitudinally extending grooves or passageways 35, and the collars 34 are provided with a plurality of spaced apart openings or apertures 36 therein. These collars are adapted to be made of -a suitable soundprooiing material such as ber glass or the like.

Mounted on the collars 34 are inserts 37, FIGURE 9, and these inserts are adapted to have a frustro-conical configuration, and these inserts 37 are provided with spaced apart apertures or openings 38 therein so as to help deaden the sound of the typewriter.

In FIGURE 5 the numeral 41 indicates a portion of a generally cylindrical body element which has a hollow interior that is generally smooth, and there is provided in the outer surface of each of the pair of body elements 41 a plurality of spaced parallel longitudinally extending passageways or grooves 39. The body elements 41 are further provided with sp'aced apart apertures or openings 40. When the parts are assembled as shown in FIGURE l for example, the end portions of the body elements 41 engage the shoulders 29 and 31 with a snug tit.

The numeral 42 indicates a cylindrical shell or tubular member that surrounds the partition 30 as well as the pair of body elements 41, and the shell 42 which may be made of a suitable material such as metal, is provided with a plurality of spaced apart apertures or openings 43. The numeral 44 indicates an outer cylindrical sleeve or tubular member that surrounds the shell 42, and the sleeve 44 is provided with openings 45 that register with the openings 43 in the shell 42.

As shown in FIGURE l0, the typewriter 21 may be of generally conventional construction and includes the usual plate or member 46 as well as the typewriter ribbon 48, and type-bars 49 which are pivotally supported as at 52, and as shown in FIGURE l1 openings or `apertures or holes 50 are provided in the frontv portion 53, and the back portion 54 may be made of a sound deadening or soundproofing material such as ber glass, and an air space 51 is provided between the front and back portions 53 and 54, and the numeral 52 indicates a pivot mounting for the type-bar.

The numeral 55 indicates a portion of the typewriter frame, FIGURE 12, and the frame 55 may includeside portions 56 that have apertures or openings 57 therein, and the numeral 58 in FIGURE 14 indicates a top portion of the typewriter frame, and the top portion 58 may also be provided with openings or apertures 57. Acoustical material as indicated by the numeral S9 may be suitably arranged within the inside of the frame adjacent the top and sides and other portions of the frame, and this acoustical material may be held in place in any suitable manner.

From the foregoing, it is apparent that there has been provided a means for dampening the sound of a typewriter or other piece of equipment or machinery, and in use with the parts arranged as shown in the drawings, it will be seen that the typewriter such as the typewriter 21 includes the platen 20 that is constructed so that sounds or noises will be dampened or minimized. rIhus, it will be noted that the pla-ten 20 includes the outer sleeve 44 of resilient material such as a suitable rubber like substance or plastic substance, and the sleeve 44 has a plurality of very small apertures or openings 45 therein that register with small openings or apertures 43 in the shell 42. Arranged within the shell 42 is a pair of spaced apart cylindrical body elements 41 which have the longitudinally extending grooves or passageways 39 in the outer portion thereof, and there is provided the small apertures or openings 4) in the body elements 4i. As shown in FIGURE 1 when the platen is assembled, a plurality of the frusto-conical inserts 37 are arranged within the body elements 41, `and these inserts 37 are adapted to Ihave small openings 38 therein. The inserts 37 surround the collars 34 which have the small openings 36 therein, and the collars 34 are provided with inwardly arranged longitudinally extending grooves 35, and these collars are mounted on the shaft 22, which has the fiber glass or acoustical material 19 thereon, and the interior of the shaft 22 is hollow as indicated by the numeral 23, and the shaft 22 has the small openings or apertures 24 therein. Certain of these members that constitute the platen are adapted to be made of soundprooiing or sound deadening material such as a suitable acoustical fiber glass or the like, and in addition the provision orC the various grooves and passageways and small openings together with the specific arrangement of the parts is such that as the typewriter is used and when the keys are manually depressed, the sounds normally produced will be absorbed or dampened by the platen so that the typewriter can be used in such a manner that a minimum amount of noise or sound will be produced. This is because the sound waves will have a tendency to be partially absorbed by the various soundproong materials that are used to make up the dilierent elements of the platen, and in addition the sound waves will have a tendency to travel through registering apertures 45 and 43 and these sound waves can enter the passageways or grooves 39 so that such sound waves will have -a tendency to become dissipated and dampened. In addition, the sound waves can then travel through the small openings 46 and enter the spaces between the inserts 37, and these inserts 37 provide batiies or reverberation chambers so as to further `dampen the sounds, and these sound waves will be further dampened by entering and passing through the apertures 36 and the collars 34 and then through the grooves 35 and the sound waves remaining may enter the interior space 23 of the shaft 22 by passing through the small openings 24. Thus, the sound waves will be directed through a circuitous path and it is to be noted that the sound waves will rst pass through small apertures and then enter longitudinally extending grooves or passageways that have their axes arranged at right angles with respect to the apertures, and from these grooves or passageways, the sound waves will enter other small apertures and then enter another area or space defined between the inserts 37, and the sound waves can then enter or pass through other small apertures and engage longitudinally extending grooves or passageways that are at right angles to the last named apertures. This construction is such that the sound waves will therefore be caused to assume different angular positions, that is, the direction of the sound waves will be constantly and continually changed or shifted and this will help to break up the sound waves so as to minimize or reduce the noise that is usually caused by such sound waves.

In addition to constructing the platen so that it will help deaden or minimize noises or sounds of the typewriter, other parts of the typewriter are likewise adapted to be soundproofed. For example, the frame 55 is adapted to be backed with yacoustical material as indicated by the numeral 59, and this acoustical material may be suitably adhesively secured 0r otherwise aixed to the inner surface of the frame wherever desired or required. Also, the member such as the member 46 is adapted to have apertures or openings 50 as well as the air space 5i, and the lback portion 54 which is adapted to be made of soundprooting material such as ber glass is such that the usual noises resulting from actuation of the keys will be minimized or prevented.

Suitable material can be used for making the various parts or elements, and such parts or elements can be made in dierent sizes or shapes as required or desired, and for example acoustical material or soundproofing materials can be used wherever the same are needed in order to help reduce the sounds that are produced.

The sizes of the various apertures or openings may be quite small so that in effect a port like construction is provided for helping to dissipate the sound waves.

While the present invention is not to be restricted to any particular theory of operation, it is thought that the construction described herein will cause the sound waves to be shifted in direction as they move from the apertures to the passageways and vice versa so as to mutiie or dampen the sounds. Thus, the sound waves will be caused to travel in a plurality of different directions at random so Ithat the sound waves will have a tendency to cancel each other out to achieve the desired effect. ln addition noises produced by vibrations will be dampened or minimized with the construction of the present invention. Also, it will be seen that as shown in FIGURE 1 air spaces are provided as for example in the grooves 39 and in the spaces between the inserts 37, and also in the grooves 35 and in the space 23, and these air spaces help provide sound barriers for further reducing the noise of the typewriter or other machine on which it is being used. Also, the end members 27 as well as the partition 30 have openings such as the openings 2S and 32 therein so that the platen will not constitute a sounding drum as is the case with conventional platens that have closed ends. The apertures such as the apertures 45 may be arranged in such a manner that they are spaced to coincide with the spacing of the typewriter keys. Also, the principles of the present invention are applicable to various types or makes of typewriters such las electric or non-electric typewriters, and in addition other types of equipment can be provided with the sound dampening mechanism of the present invention in addi- 'tion to typewriters. With the present invention the sound waves can be converted into other forms of energy such as heat energies which can be dissipated, and the porosity and absorotivity of the various parts help dampen the sounds. Other types of equipment that can be provided with the mechanism of the present invention are bookkeeping machines, adding machines, printing machines or the like and the present invention for example can be used in any type of equipment that uses a platen. Due to the porous construction, the sound waves will have to pass through such small openings or apertures or pores whereby the sound waves will be converted to heat due to the friction that is generated, so that the typewriter or other equipment can be used more quietly. The batiies or inserts 37 are adapted to be perforated and made of sound absorbing material. Acoustical material such as fiber glass can be arranged within certain of the spaces of the platen so as to help dampen the noises or sounds. Also, the end members 27 and partition 30 can be made of a sound proof material. The construction such as that shown in FIGURE 11 is such that the air space 51 and blanket of fiber glass or plastic back portion 54 and the openings 50 help reduce the noise level as the typewriter is used. The small apertures or pores may be made quite small so that in fact they are invisible and such invisible porous openings will help air soften the noises from the typewriter.

With the parts arranged as shown in FIGURE l, it will be seen that there is provided a plurality of different passageways and apertures for the sound waves to pass through, :and these sound waves will thus intermingle and intermix and bounce against each other as well as bounce against the various wall surfaces of the platen so as to help dissipate each other and cancel each other out, and in addition the sound waves will have their wave lengths changed as well as the frequency thereof so that the end result will be Ia lessening in the noise produced by the typewriter.

It is to be noted that a typewriter or other piece of equipment' made according to the present invention includes a mounting means which will insure that a quiet operation thereof is insured. Certain of the parts are made of resilient material such as rubber wherein noises will be sealed out, and also such resilient material will help prevent the noises from being transmitted, so that sound barriers are provided whereby a remarkably quiet machine is available. In addition, the parts are ruggedly constructed so that a rigid and tight fitting arrangement is insured which will also contribute to the quietness since there will be less subject to distortion so as to reduce the likelihood of developing squeaks and rattles.

The acoustical material such as the acoustical material 56 may have pores therein so as to help dampen the sound. The acoustical material may be of any suitable variety and as for example fiber glass can be utilized. This acoustical material will help dampen or labsorb the sound waves.

In addition, the fiber glass 19 that surrounds the shaft 22 is also of the type that has small pores therein. In addition, the frame struts and other` parts can be dampened by suitable mastic insulation material. The fiber glass 19 on the hollow metal shaft 22, may be approximately one-eighth of an inch thick.

As shown in FIGURE 13 and in FIGURE 14, an air space is adapted to be provided between the outer frame work of the typewriter and the inner acoustical material.

The end members 27 may be secured to the shaft 22 by means of set screws or securing elements 27', or else a keyway slot arrangement including male and female parts can be used to hold these members connected together.

Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

What is claimed is:

1. In a typewriter, a hollow shaft provided with a plurality of spaced apart apertures therein, a covering of acoustical material on said shaft, a platen mounted on said shaft and said platen including a pair of spaced parallel end members affixed to said shaft, a circular partition interposed between said pair of end members and said partition being mounted on said shaft, -said partition and rend members being provided with opposed shoulders, there being a plurality of spaced apart apertures in said end members and partition, cylindrical collars mounted `on lsaid shaft and said collars being interposed between said partition and end members, and said collars having a plurality of spaced apart Iapertures therein, a plurality of frustro-conical inserts mounted on said collars, apertured cylindrical body elements surrounding said inserts, the interior of said body elements being smooth and the exterior of said body elements having a plurality of spaced parallel longitudinally extending passageways, the ends of said body elements engaging said shoulders, a cylindrical rapertured shell surrounding said partition and body elements, and an outer cylindrical sleeve surrounding said shell.

2. The structure as defined in claim 1 wherein said sleeve has a plurality of apertures therein that register with apertures in said shell.

3. In a typewriter, a hollow shaft provided with a plurality of spaced apart -apertures therein, a covering 0f yacoustical material on said shaft, a platen mounted on said shaft and said platen including a pair of spaced parallel end members axed to said shaft, a circular partition interposed between said pair of end members and said partition being mounted on said shaft, said partition and end members being provided with opposed shoulders, there being a plurality of spaced apart apertures in said end members and partition, cylindrical collars mounted on said shaft and said collars being interposed between said partition and end members, and said collars having a plurality of spaced apart apertures therein, a plurality of frustro-conical inserts mounted on said collars, apertured cylindrical body elements surrounding said inserts, the interior of said body elements being smooth and the exterior of said body elements having a plurality of spaced parallel longitudinally extending passageways, the ends of said body elements engaging said shoulders, a cylindrical apertured shell surrounding said partition and body elements, and an outer cylindrical sleeve sur rounding said shell, said typewriter -further including a strike bar of hollow construction that has a plurality of spaced apart openings therein, and said typewriter further including a frame, and apertured acoustical material aihxed to the inner surface of said frame.

References Cited in the iile of this patent UNITED STATES PATENTS 1,010,698 Smith Dec. 5, 1911 1,680,124 Waldheim Aug. 7, 1928 2,097,588 Dobson Nov. 2, 1937 2,142,260 Thompson Ian. 3, 1939 

